title: A cytosine-rich DNA decorated gold nanoparticles surface enhanced Raman-scattering platform for sensitive and selective detection of silver ions.
abstract: In this work, we developed a label-free, homogeneous surface-enhanced Raman-scattering (SERS) platform for the rapid, simple and sensitive detection of Ag(+) by using the unmodified gold nanoparticles (AuNPs). It utilizes the different absorption properties of single-strand DNA (ssDNA) and double-strand DNA (dsDNA) on citrate-coated AuNPs and specific interactions between Ag(+) and cytosine-cytosine pairs. In the presence of Ag(+), the structure of ssDNA containing rich cytosine will form a duplex, resulting in the salt-induced aggregation of gold nanoparticles; the corresponding SERS signal transduction can be observed due to the plasmonic coupling of metallic nanoparticles. The assay possesses a superior signal-to-background ratio as high as ∼35.8 with a detection limit of 15 nM. This approach is not only rapid and convenient in operation, but also shows excellent selectivity, which makes it possible to detect Ag(+) in actual samples.
authors.affiliation: State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University.
authors.forename: Hai-Ying
authors.initials: HY
authors.lastname: Qiao
authors.forename: Mei-Lan
authors.initials: ML
authors.lastname: Hong
authors.forename: Xue
authors.initials: X
authors.lastname: Tian
authors.forename: Li-Jiao
authors.initials: LJ
authors.lastname: Huang
authors.forename: Xia
authors.initials: X
authors.lastname: Chu
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D003596:Cytosine; D004247:DNA / Q000737:chemistry*; D060766:Drinking Water / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D012834:Silver / Q000032:analysis* / Q000737:chemistry; D013059:Spectrum Analysis, Raman; D013499:Surface Properties
chemical_list: D060766:Drinking Water; D012834:Silver; D006046:Gold; D003596:Cytosine; D004247:DNA